Vertical acid sludge mill



Feb. 6, 1951 R. c. HOPKINS VERTICAL ACID SLUDGE MILL 2 Sheets-Sheet 1Filed Dec. 15, 1945 Roberf 61 Hopkins Feb. 6, 1951 R. c. HOPKINS2,540,883

VERTICAL ACID SLUDGE MILL Filed Dec. 15, 1945 2 Sheets-Sheet 2 Fi 5 4 3Roberl' C Hopkins Patented Feb. 6, 1951 UNITED STATES PATENT OFFICE 3Claims.

The invention relates to rotary mills for the processing of acid sludge,and the like, and more particularly to a vertical type of mill in whichthe bearings are located entirely outside oi the milling chamber.

In the processing of fuels made up of acid sludge, a refineryby-product, it is found that this is not only the most corrosivesubstance encountered anywhere in the industry, with the exception ofnitric acid pickling solution, but that it i also errosive on account ofthe near solids contained in the acid sludge mass.

Applicant has patented, and has in operation, a number of types ofhorizontal mills, but it has been found by experience that the bearingsand shaft of such mills wear out from the combined action of the acidand the solids, or near solids, contained in the acidulated sludge.

The object of the present invention is to provide a mill for theprocessing of acid sludge, bunker C oil and similar materials, whichwill overcome the above mentioned difiiculties and disadvantages in theuse of the present types of mills.

Another object is to provide a mill of this character in which thebearings are located entirely outside of the milling chamber so as notto come into contact with the acid sludge or other material beingprocessed in the mill.

A further object is to provide a rotary mill in which oil under pressureis circulated through the bearings.

Still another object of the invention is to provide such a mill in whichoil under pressure is forced through the packing chamber surrounding theshaft at the outlet end of the mill, setting up a pressure to resist theout-flow of the acid sludge from the mill through the packing chamber.

A further object is to provide a vertical mill in which the pressure inthe milling chamber is upward thereby relieving the bearings of aportion of the load.

A still further object is the provision of a mill of the type referredto in which the parts subject to vibration are low enough upon thefoundation to prevent any troublesome vibrating condition.

Another object is to provide a vertical mill adapted to any kind ofmotor drive or vertical steam turbine drive and which may be belt drivenas well as directly by the motor.

Still another object of the invention is to provide a mill of the typereferred to in which all parts are easily accessible for inspection,adjustment or repair.

The above objects, together Will others which will be apparent from thedrawings and following description, or which may be later referred to,may be attained by constructing the improved vertical acid ludge mill inthe manner illustrated in the accompanying drawings, in which;

Figure l is a side elevation of a mill embodying the invention;

Fig. 2 a top plan view of the mill shown in Fig. 1;

Fig. 3 an enlarged, vertical, longitudinal, sectional view through themilling chamber and bearings; and

Fig. 4 a transverse sectional view through the milling chamber, taken ason the line 4-4, Fig. 3, and drawn on a larger scale than Fig. 3.

The mill is mounted within an upright frame, indicated generally at l0,and the vertically disposed mill housing indicated generally at H, isshown supported upon the horizontal bottom plate 12 of the frame andhaving its lower end communicating centrally with the curved inletpassage 3, to which is connected an inlet pipe i4 leading from anysuitable source of acid sludge, bunker C oil or other material underpressure which is to be processed in the mill.

The upper end of the mill housing H is pro vided with an eccentricdischarge opening I5 communicating with the upwardly inclined outletopening IB formed in the casting indicated generally at I7 andcommunicating at its outer end with the discharge pipe l8 through whichthe processed material may be conveyed to any desired location.

The casting IT includes a base portion I9 which is supported upon theupper end of the mill housing II and has the concentric packing box 20formed thereon. A disc platform 2|, concentric with the base I9, isformed upon the upper end of the casting I! and has a concentricstufiing box 22 depending therefrom.

The upright cylindrical bearing chamber housing 23 is mounted upon theplatform 2| and may be attached as by the screw 24 to an angular crossbrace 25.

Upper and lower ball bearings indicated generally at 25 and 21respectively are located in the upper and lower ends of the bearingchamber housing and a stufling box 28 may be provided at the upper endof the bearing chamber housing 23 and surrounding the vertical shaft 29which extends longitudinally through the mill.

A collar or shoulder 30 is formed or fixed upon the shaft 29 in contactwith the upper ball bearing 26 so that at least a part of the load or"the shaft, and milling apparatus to be later described, is carried. bythis bearing.

The shaft extends downwardly through the bearing chamber and through thelower bearing 2'! and the stufiing box 22 and packing box 23, and thelower portion of the shaft is preferably reducedg-ini-diameterasat 3 ianol extends longitudinally entirely through the millhousingfil,terminating adjacent to the inlet end thereof.

' A rotary cutting unit is carried upon the reduced lower end portion ofthe shaft and may be in the form of a plurality of disc saws. For-thispurpose a hub 32 may be fixed upon the. shaft as by the key 33. Ashoulder 3% is formed upon the shaft, at the point where-'itis-reducedto engage the upper end of the hub to position the same relative to theshaft and an annular flange, 35,is formed upon the upper end of the hub.

Alplurality of ldiscsaws 135 is mounted upon the hub-,andextends fromthe flange to aipoint :nearZthe lowerend .ofthehub, at which point airingffiange-S'i, may be located aroundthe hub and clampedqagainsttheadjacent end of the gang of disc saws as byanut 38 threaded upon theiloweriportionof thehub thus clamping the. gang of saws tightly betweenthe flange i355 and the i ringnflangeifil. Anut-S'B may be'located-uponthe threaded lower end portion 453 of the-shaft .fer lockingthenutfisinadjustedipositioniupon =-the h-ub.

A plurality of attrition chambers ii maybe io'rmediwithiwthehousingbymeans of longitudinal partition: walls 52' and: tranverse partitionWalls Ed t extending qinward from I the housing to ia poi'ntcloselyadjacentito theperipheries of the -gang of-rsaws 3t.

Forfthejpurpose of maintaining a constant ciricu lation"oidubricating.oil through and around ithe bearings as and Zlymeans may be provideditor-pumping oil-under pressure through the hearing chamber 2-3,-and'inthe drawings this means sis:shownasan"oils'pump indicated generally athaving ane' oil :pipe =35 connected thereto for pumping oil into thebearing chamber as at lt,

' "and al branch-of-sai'd. pipe for pumping oil above i theuppenlbearing 'tt; and. a return pipe for re- "turning 1 oil from -thebearing chamber to the pumpi i i.

fIfdesired, a pipe se may lead from the pump M 'or frcm a secon'd pu1np,ior pumping oilinto the ceritral portion or the packing chamber 629 inorder to maintain a pressuretherein to resist itheput-fioiv of acidsludgearoun'd the shaft at the i upper end' of the mill housing andintothe packing chamber.

T-his 'vertical mill is adaptedto any kind of motorfidrive,=verticalsteam turbine drive or may i beibelt driVen. Fo'r the purpose ofillustration, a motor 59 is shownfdir'ectly{connectedto the tipper endoftheshaft, preferably through a a'clutch' 5 i. A pressuregauge may beprovided Lfor -the milling chamber as wellas a thermometer 53, and asight gauge 56 may beprovided upon -the bearing=chamber to indicatetheoil level therein.

From theabove it will be evident that'the -up1zier -ball bearingZficarries at-least a part of the weight-of the: shaft and the sawassembly, and part o f the-weight: thereof will be supported by' thupward-pressureof the material being rn-illeti *which enters =the millat the lower end lubricant in the bearing chamber'has a tendency :tokeep the lubricant in a state of uniform mixture as well as to hold itat a minimum tempera- -ture, the-' running shaft and bearings tending towarm up the lubricant while the circulating pump and the volume of oilact as a temperature adjustment. 7

.I. -cl-aim: V

1. Apparatus of the character described comprising avsupport,verticallyrspaced ball bearings carried bythe support, a bearing chamberenclosing the bearings an'd means "for circulating lubricant under 1pressure through the bearing chamber, a'cantilever rotatable, verticalshaft having its upper end .portionjournalled in said bearings, the freeend of the'shaft extending downwardly beyond the bearing: rotor mountedupon the freeendof: the, shaft, a housing enclosing the rotor, a packing17box' surroundingthe shaft at the upper :end of the housing; means foradmitting oil underipressure' to the packingjbox and means, for.passingliquid' upwardthrough: the

housing thereby-supporting a portion -of the load of the, shaft androtor.

rotary mill including .a'vertical, cylindrical mill housing havingacentral inlet at its lower end and an eccentricroutlet at its upper-end,a vertical shaftlocatedthrough the upper ,end of the housing :andterminating at-its lower end within said inlet 2" cylindrical gangofdisc saws imounted upon the-shaftwithin the mill housing,-a-packing-box surrounding the shaitat the upper end of the housing, aplatform surroundingthe i shaft; ,at-a point spacedv above saidpacking-box, means upon'the top. of -the housing supporting :the;platformiinspaced relation above said, packing 1 ,box panuprighticylindrical 'bearingchamber mounted upon said platformand-surrounding the shaft, spaced :ball hearingsiiniopposite;-ends ofthe bearingi chamber, the shaft'being journa'lled in said ball bearings,a stufiing boxat each end of the bearing, chamber and, meansfor-maintaining :the abearing chamber filled with oil under pressure.

-3.;'A rotaryjmilli-including;a vertical, cylindricalmill-housinghavingagcentral inlet at its lower end g-and, an .eccentricioutlet tat; its 1 upper end, ;a

vertical shaft located through the upper-j end'of the housing a anditerminating at 1 its lower end Withinsai'd; in1et,-i@ajcylinidricahgang of disc" saws mounted; uponnthe: shaft Within? the;mill housing,

a packing box surrounding the shaft atthe: upper end of sth'e 'housingfa:platform surrounding the shaft sat :a pointi'spaced above-said. packingbox,

" means upon :the topsof the housing supporting the platform in -spacedrelation above said; packing box, an upright cylindrical bearing chambermounted upon said-platform-andsurroundingthe shaft, spaced ball hearings:in opposite ends of i the bearing chamber, the :shaft being 3journalled in said ball bearings, 'a' stuiiing box att-each' -end ing"the -bear ing cham-ber filled' with oil under pressure, and means foradmitting oil under pressure to the packing box.

ROBERT C. HOPKINS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Number 6 Name Date Austin June 1, 1926Teague Apr. 12, 1927 Cuniff Jan. 1, 1929 Eppenbach Apr. 22, 1930 RaftsonJan. 15, 1935 Lord June 16, 1936 De Bethune Apr, 20, 1937 Bowen Dec. 28,1937 Doering Oct. 4, 193 8 Fromm Dec. 13, 1938 Hopkins Jan. 27, 1942Feight July 10, 1945

